Lock.



A. H. SPARLING.

LOOK. APPLICATION FILED JAN.18,1'907.

I'HE mum's PzrERs co wnsuma-mu, n. c

PATENTED APR, 23, 1.908,

AUGUSTUS HENRY SPARLING, OF ALIGARH, INDIA.

LOCK.

Specification of Letters Patent.

Patented April 28, 1908.

Application filed January 18, 1907. Serial No. 353,000.

To all whom it may concern:

Be it known that I, AUGUSTUS HENRY SPARLING, a subject of the King of Great Britain, residing at Aligarh, British India, have invented new and useful Improvements in Locks, of which the following is a specification.

The object of this invention is to make the picking of the lock a matter of greater difficulty than heretofore. For this purpose there is fitted Within the lock a standard or bar against which lugs on the levers of the lock are arranged to very nearly impinge when they are raised by the key into the position in which the stump on the sliding bolt passes through the gatings of the levers as hereinafter more fully described.

In order that the details of construction and action of my invention may be more clearly understood reference is made to the accompanying drawings in which:

Figure 1 is a perspective view of the interior of a lock with my invention applied thereto, part of the casing being removed. Fig. 2 is a plan showing the stump passing the gatings and all of the levers nearly impinging on the standard.

Within the lock is fixed or formed integral with the body 9 a standard or stud 25 in such a position that when the levers 27 are raised during the operation of looking or unlocking the lock by the proper key, the lugs 26 on all of the levers 27 stand slightly clear of such standard or stud 25 (Fig. 2) during the passages of the stump 29 through the gatings of the levers which gatings may be made of only just sulficient Width to enable the stump 29 to pass.- But in the event of an attempt being made to operate the lock by means of a key which difiers even toa very slight extent from the proper key, and one (or more). of the lugs 26 on the levers 27 is thereby raised to a very slight extent beyond the others, it will jam against the standard or bar 25 and further movement of.

the key or of the levers 27 will be thereby prevented. It will be seen that the standard or bar 25 prevents any further movement of the key and levers immediately any one of such levers impinges upon it thereby forming a safeguard against picking by the method of feeling.

While the number of levers and the shape of the key may be altered to suit various circumstances.

I claim:

1. In a look, a fixed standard or stud 25 against which one or more lugs 26 on the levers 27 of the lock impinge when any one or more of the said levers is or are moved beyond the position in which the stump 29 of the bolt 22 is capable of passing through the gatings, substantially as described and for the purpose set forth.

2. In a lock, means for blocking the levers 27 and preventing the further movement of the key in the event of any of such levers being raised beyond the correct osition to permit of the stump 29 of the Eolt 22 passing through the gatings which means consists of a standard or stud 25 fixed to the body of the lock, and lugs 26 on the levers 27 so situated that when the said levers are raised into the correct position for the stump 29 to pass the gatings the said lugs come nearly, but not quite, into contact With said standard 25, but if one or more of said levers is raised beyond that position it comes immediately into contact with the said standard and further movement of the key is thereby pre vented, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

AUGUSTUS HENRY SPARTJING- Witnesses:

STEPHEN EDWARD GUNYON, WILLIAM ANDERSON SMITH. 

